1 # SPDX-License-Identifier: GPL-2.0-only
3 tristate "NILFS2 file system support"
6 NILFS2 is a log-structured file system (LFS) supporting continuous
7 snapshotting. In addition to versioning capability of the entire
8 file system, users can even restore files mistakenly overwritten or
9 destroyed just a few seconds ago. Since this file system can keep
10 consistency like conventional LFS, it achieves quick recovery after
13 NILFS2 creates a number of checkpoints every few seconds or per
14 synchronous write basis (unless there is no change). Users can
15 select significant versions among continuously created checkpoints,
16 and can change them into snapshots which will be preserved for long
17 periods until they are changed back to checkpoints. Each
18 snapshot is mountable as a read-only file system concurrently with
19 its writable mount, and this feature is convenient for online backup.
21 Some features including atime, extended attributes, and POSIX ACLs,
22 are not supported yet.
24 To compile this file system support as a module, choose M here: the
25 module will be called nilfs2. If unsure, say N.